A Warning About Trunk Systems

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This is a warning about trunk systems.

There are issues that can arise when trying to setup your scanner to monitor trunked radio traffic.

Today’s podcast contains some hints to help you keep your sanity when programming your scanner for large trunk systems with multiple sites.



What You Need To Know

  • runk system has a couple of different components that make it work.
  • We need a transmitter or tower to receive or tune to.
  • We need a control channel that tells the scanner what talk groups are active
  • Our scanner will move to voice channels when talk groups are active.
  • Talk groups are segments of users or departments on a trunked system.
  • Trunk systems can have multiple sites. Trunk systems can be large, they can be small. They can be multi-level, multi county, multi state, single state. They can be small systems ranging inside of a building to ranging across thousands of miles, but they all start with a single site.
  • A “site” in Radio Reference and a “site” on paper are not the same as a transmitter site. It can be, but it shouldn’t be thought of that way.
  • We can also have sites and layers set up based on who uses them.
  • To program our scanners correctly, we need to know if talk groups are segmented on specific layers (aka sites) or if they are shared across multiple sites
  • Talk groups only appear on sites if there are users affiliated on those sites. This helps manage spectrum and only required talk groups are using valuable RF resources.
  • Don’t expect a user that’s 100 miles away from you to be on the site you are listening to if the selected layer doesn’t cover where they are.
  • It’s very important to understand where the talk groups are showing up on these systems.


Are you looking for your first scanner radio?

Download our new e-guide, “5 Thinks You Need to Know Before Buying Your First Scanner”.   This free PDF is about 30 pages long and has 5 things you should look for, plus a few extra bonus items to make sure you make an educated purchase.

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